Dear Dr. Sanford:
I read your article from top to bottom and back again.  It is that good.
I think that when we (ALL OF US) talk about bee mites,  that it is imperative that
we make the distinction between  Tracheal Bee Mites and Varroa.
I have had little experience with tracheal bee mites (apart from dissecting bees and
looking for the presence of mites).  I have seen obvious signs of mite infestation,
the reason that led me to dissect some samples but I am sure that they could have
missed them in many colonies that did not reveal signs of infestation and thus miss
their presence all together. So far my experience with tracheal mites.
Regarding Varroa:
I have been studying Varroa mites for almost 14 years.  During this time, I have
seen one unique characteristic about Varroa mites.  They KILL untreated colonies.
In my humble opinion, developing resistant honey bees will probably be one of the
greatest achievements in beekeeping if that is ever accomplished.  Until 1 July
1996, I lost 90% of bee colonies that I owned to Varroa even though I was treating
them with the accepted bee mite control of these days and six out of eleven that I
bought subsequently.
Since 1 July 1996, I soon lost 3 colonies left untreated (controls) while I treated
23 others with mineral oil.  Some of the colonies treated with mineral oil succumbed
due to reasons not entirely related to mite infection (too small, nosema,
pilfering).  At the end of on year of continuous mineral oil treatment, I
discontinued treatment on three strong, seemingly healthy colonies.  All three
perished before the end of the summer, including a colony which I had owned for
three years (I was hoping that it had developed resistance).
In essence, I would give, (as the saying goes) an arm and a leg to find an untreated
colony that survives beyond a year if infected with Varroa mites.  Precisely because
I support the
idea that development of resistant strains of honey bees would be the ultimate
achievement in this area.
In conclusion,  I considered necessary to share my experience and knowledge with
Varroa mites because I feel that there is definite pathogenicity distinction between
the two mites and that it needs to be stressed.  While it might be possible that
certain races of honey bees have developed "resistance" to tracheal mites, one can
not say the same for Varroa mites with certainty.  Hence, beekeepers who trust that
their honey bees will develop resistance to Varroa mites ( without treatment) are
setting themselves for disappointment and severe losses.
Please remember that I am not in disagreement with you.  I am merely stating my
observations of nearly 14 years studying Varroa mites.
Best regards.
Dr. Rodriguez
Virginia Beach, VA